Missions to Venus and Mercury

As one of the first planets to be visited by spacecraft, Venus witnessed many failed attempts at missions. However, more than 20 have been successful. Venus is a necessary waypoint for missions to Mercury, of which there have been only two.

Active missions

Akatsuki あかつき

a.k.a. Venus Climate Orbiter, Planet-C (JAXA)

Launch: May 20, 2010Orbit insertion: December 7, 2015

Akatsuki (あかつき, 暁?, literally "dawn"), formerly known as the Venus Climate Orbiter (VCO) and Planet-C, is a Japanese space probe which was intended to explore Venus. Akatsuki was Japan's first planetary exploration mission since the Nozomi probe, which was launched in 1998 which failed to go into a Mars orbit in 2003 as planned. The mission reached Venus on December 7, 2010 (JST) but failed to enter orbit around the planet, and thus ended up in a heliocentric orbit. It had been intended to conduct scientific research for two or more years from an elliptical orbit around Venus ranging from 300 to 80,000 km (190 to 49,710 mi) in altitude. In December 2015, Akatsuki successfully entered orbit around Venus using only its attitude control thrusters. It is now in an elliptical orbit ranging from 400 to 440,000 km in altitude.

Future missions

BepiColombo

Mercury Orbiter (ESA and JAXA)

Launch: July 9, 2016 (planned)Orbit insertion: January 2024 (planned)

BepiColombo is a joint mission of the European Space Agency (ESA) and the Japanese Aerospace Exploration (JAXA) to Mercury. The mission is composed of two satellites: the Mercury Planet Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO). The mission will perform a comprehensive study of Mercury's magnetic field, interior structure, and surface. The mission was named after Giusepppe Colombo, a scientist, engineer, and mathematician who implemented the first interplanetary gravity-assist maneuver during the 1974 Mariner 10 mission, a technique now commonly used by planetary probes. After an Earth flyby in 2018 and a series of Mercury flybys in 2019–2023, orbit insertion around Mercury is planned for January 2024.

MESSENGER (an acronym of MErcury Surface, Space ENvironment, GEochemistry, and Ranging, and a reference to Mercury being the messenger of the gods) is a robotic NASA spacecraft orbiting the planet Mercury, the first spacecraft ever to do so. MESSENGER became the second mission after 1975's Mariner 10 (launched by NASA on November 3, 1973) to reach Mercury when it made a flyby in January 2008, followed by a second flyby in October 2008, and a third flyby in September 2009. Then MESSENGER entered orbit around Mercury on March 18, 2011. The MESSENGER mission ended in April 2015 after the spacecraft used the last of its maneuvering propellant and its orbit decayed, resulting in the spacecraft crashing into the surface of Mercury.

Venus Express

Successful Venus Orbiter (ESA)

Venus Express (VEX) was the first Venus exploration mission from the European Space Agency (ESA). Launched in 2005, it arrived at Venus in April 2006 and continued to send scientific data back from its polar orbit around the planet until contact was lost on November 28, 2014, during an orbit maneuver to raise the spacecraft's altitude in the hopes of extending the mission's lifetime, which exhausted the spacecraft's remaining fuel. The mission was officially declared over by ESA on December 16, 2014.

Cassini-Huygens

Successful Saturn orbiter (NASA)

Cassini-Huygens used the planet Venus for two gravity assists, leading up to Earth and Jupiter flybys and its eventual arrival at Saturn. The flybys were notable for the failure to detect lightning at Venus.

Magellan

Successful Venus orbiter (NASA)

Launch: May 4, 1989Venus orbit insertion: August 10, 1990

By the end of its mission, Magellan had mapped over 98% of Venus at a resolution of 100 meters or better using Synthetic Aperture Radar (SAR). Images were acquired over three “cycles” at different geometries, permitting stereoscopic views of parts of the surface. Magellan also acquired topography, slope, radiometry, and scatterometry measurements of the surface over a mission spanning five years.

Vega 1

Successful Venus probe and Comet Halley flyby (USSR)

As Vega 1 swung by Venus, it deployed a 2.4-meter probe into the atmosphere. The probe deployed a balloon almost immediately upon entering the atmosphere. The balloon, which measured temperature, pressure, wind velocity and visibility of the atmosphere, covered 9,000 kilometers in 47 hours before it burst. The probe took readings of the atmosphere as it descended to the surface.

Venera 13

Successful Venus orbiter and lander (USSR)

Launch: October 30, 1981Venus arrival: March 1, 1982

Venera 13 returned the first color images from the surface of Venus, landing at 7.5° S, 303° E. A drilling arm collected a sample that was examined by an onboard x-ray fluorescence spectrometer to determine its composition. The lander survived 127 minutes before giving in to the extreme heat (457°C) and the tremendous pressure (84 times the pressure at sea level on Earth).

Venera 11

Successful Venus orbiter and lander (USSR)

Launch: September 9, 1978Venus arrival: December 25, 1978

Details about Venera 11 are sketchy; however, the spacecraft did make a soft landing on the surface, and sent back evidence of thunder and lightning as well as the presence of carbon monoxide in the lower altitudes. Data was transmitted back to Earth for 95 minutes before the lander rotated out of range of the orbiting relay.

Venera 12

Successful Venus orbiter and lander (USSR)

Launch: September 14, 1978Venus arrival: December 21, 1978

Launched three days after Venera 11, Venera 12 actually made it to Venus four days before the other spacecraft. Venera 12 was designed to study the atmospheric composition and clouds of Venus. The lander transmitted 110 minutes of data before the planet rotated out of range of the orbiting relay.

Pioneer Venus 2 (Pioneer Venus Multiprobe)

Four successful Venus probes (NASA)

Launch: August 8, 1978Venus arrival: December 9, 1978

Pioneer Venus 2 consisted of four separate atmospheric probes; one large probe 1.5 meters in diameter, which deployed a parachute to slow its descent, and three small probes (0.8 meters across) which plunged straight through the atmosphere. The large probe was released from the spacecraft bus on November 16, 1978. The three smaller probes were released four days later. All of the probes arrived at Venus on December 9, 1978. Each probe took atmospheric measurements as they descended through the cloud layer. One of the probes survived to transmit data for over an hour after it impacted with the surface. The spacecraft bus that carried the probes also had instruments and made measurements in Venus’ uppermost atmosphere before burning up.

Pioneer Venus 1 (Pioneer Venus Orbiter)

Successful Venus orbiter (NASA)

Launch: May 20, 1978Venus orbit insertion: December 4, 1978

Pioneer Venus 1 carried 17 experiments, including a radar mapper. Scientists used the radar to map nearly the entire planet, resolving features as small as 80 kilometers. The spacecraft remained in orbit until August of 1992, when it used up all its fuel and burnt up in the atmosphere.

Venera 10

Successful Venus orbiter and lander (USSR)

Launch: June 14, 1975Venus landing: October 25, 1975

The Venera 10 spacecraft separated into two different sections, an orbiter and a lander, on October 23, 1975. Two days later, the lander touched down on the surface of Venus 2,200 kilometers from the Venera 9 lander, somewhere within a 150 km radius of 15.42° N, 291.51° E. With the orbiter acting as a relay, the lander transmitted images from the surface as well as data about clouds and the surface environment.

Venera 9

Successful Venus orbiter and lander (USSR)

Launch: June 8, 1975Venus landing: October 22, 1975

The Venera 9 lander separated from the orbiter on October 20, 1975. Two days later, the lander touched down and became the first spacecraft to transmit a picture from the surface of another planet. It landed within a 150-kilometer radius of 31.01° N, 291.64° E. In addition, the lander sent back information on the Venusian clouds, atmospheric composition, and light levels. All of the information was transmitted from the surface to the orbiter, which then relayed the signal to Earth. Besides acting as a data relay, the orbiter also studied the cloud structure of the planet.

Failed Venus lander attempt (USSR)

Venera 8

Successful Venus lander (USSR)

Launch: March 27, 1972Venus landing: July 22, 1972

Upon Venus arrival Venera 8 used aerobraking to decelerate, and then deployed a parachute. A refrigeration unit cooled the spacecraft's components, protecting them from the intense heat as the lander descended to the surface. Once on the ground, the spacecraft transmitted data for 50 minutes, confirming a very high surface temperature and crushing atmospheric pressure. It also measured the light level on Venus’ surface and found it suitable for surface photography, setting the stage for the images to be returned by Venera 9, 10, 13, and 14.

Failed Venus lander attempt (USSR)

Venera 7

Successful Venus probe (USSR)

Launch: August 17, 1970Venus arrival: December 15, 1970

When Venera 7 arrived it deployed a parachute and began its descent to the surface. Scheduled to take 60 minutes to descend, the probe touched down in only 35 minutes, possibly because its parachute may have been damaged by high winds. The spacecraft then transmitted a weak signal for 23 minutes, becoming the first spacecraft to return data from the surface of another planet. It reported surface temperatures of 475°C and atmospheric pressures 90 times greater than Earth's.

Venera 6

Successful Venus probe (USSR)

Launch: January 10, 1969Venus arrival: May 17, 1969

Twin to Venera 5, Venera 6 arrived just a day after its sister ship. Once at Venus, the spacecraft deployed a parachute and descended through the atmosphere. Scientists on Earth received 51 minutes of data as the probe descended 38 kilometers (almost 24 miles). The spacecraft was damaged the crushing pressure before it reached the surface.

Venera 4

Successful Venus probe (USSR)

Launch: June 12, 1967Venus arrival: October 18, 1967

When Venera 4 arrived at Venus it dropped several instruments, including a thermometer and a barometer, into the atmosphere. It received data back from these probes before it deployed a parachute and descended into the atmosphere itself. Preliminary readings seemed to indicate that the probe had taken measurements all the way down to the surface, but later analysis suggested that the crushing atmosphere damaged the spacecraft at an altitude of almost 25 kilometers. The probe revealed an atmosphere made almost entirely of carbon dioxide, with temperatures ranging from 40°C high up in the atmosphere to 280°C closer to the surface, and pressures ranging from 15 to 22 atmospheres.

Venera 3

Venus probe attempt (USSR)

Launch: Nov. 16, 1965Venus impact: March 1, 1966

Venera 3 was the first spacecraft to land on (impact) another planet, but no data was returned. It is believed that Venus's thick atmosphere and crushing pressure destroyed the spacecraft on its way to the surface.

Sputnik 20

Failed Venus probe attempt (USSR)

Mariner 2

Successful Venus flyby (NASA)

Launch: August 27, 1962Venus flyby: December 14, 1962

Mariner 2 was the first spacecraft to successfully fly by Venus, at an altitude of 34,773 kilometers. The spacecraft discovered ground temperatures as high as 428°C (800°F). Other instruments detected no water vapor in the atmosphere or any evidence of a magnetic field around the planet. Radio contact was lost on January 3, 1963.